Microsoft is inviting developers to take part in a beta program testing out an updated version of the SideShow application it introduced as part of Windows Vista.

SideShow is an application designed for Windows Vista laptops that enables users to be able to view email, instant messages and RSS-type information on a screen embedded in the outside of the lid. This means laptop owners won’t be inconvenienced by having to open their laptop and fire up Windows in order to check for new mail or news feeds.

As well as being a convenient way of checking information, it’s also a neat way of preserving a laptop’s battery. Information can be viewed on the secondary SideShow screen regardless of whether the laptop is fully powered up, in sleep mode or switched off.

SideShow makes use of the Gadgets in Vista – small desktop items that display stock tickers, news headlines, the time, Windows Mail messages and so on.

To date, the only company that has released a laptop product that uses SideShow is Asustek – Microsoft’s hardware partner in developing the original concept.

However, details about Windows SideShow on Microsoft’s website state that the software is not just designed for laptops and is applicable for use on gadgets. Mobile phones are one such likely use – Apple’s iPhone uses Gadget-like Maps & Apps – while Microsoft also foresees SideShow being used in displays such as digital photo frames.

According to a blog on Microsoft’s MSDN (Microsoft Developer Network) earlier this month, the next version of Vista SideShow will include a QVGA portrait user interface designed for remote controls and will support both USB and Bluetooth devices. This is likely to add to the appeal of SideShow-enabled devices both for the home and for mobile use.

Motorola's Razr2 range of mobile phones has external touchscreens with which to control music and video playback and to accept and reject calls. While we’ve yet to hear Microsoft say as much, we believe it’s possible SideShow could be used to enable similar functions on, say, Windows Mobile 6.0 smartphones.

The other obvious use is for a remote control-enabled laptop to be used in the home for entertainment purposes. The external Sideshow display would indicate the track currently playing and be used to jump to other items in the Media Player library, without the user having to have the laptop lid open and the full Windows Media Player application active.

While primarily aimed at hardware and device manufacturers, Microsoft says it will allow anyone to take part and offer feedback about the next version of SideShow. To be included in the beta program for Windows SideShow Device SDK v1.4 or for more details about what it will include, click here.

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